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1.
Conference Reports: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E‐mail to macromol@wiley‐vch.de.  相似文献   
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A case of actinomycotic brain infection in a juvenile patient is described. Cases of actinomycosis affecting the head and neck are rare, particularly in juvenile patients. In this case complete resolution of the infection was achieved by means of surgical treatment and prolonged antibiotic therapy. The authors emphasize the importance of a combined approach for treatment of this unusual brain infection and stress the difficulties involved in the diagnosis of this pathology. Received: 3 November 1997  相似文献   
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Von Willebrand factor, platelets and endothelial cell interactions   总被引:13,自引:0,他引:13  
Summary.  The adhesive protein von Willebrand factor (VWF) contributes to platelet function by mediating the initiation and progression of thrombus formation at sites of vascular injury. In recent years there has been considerable progress in explaining the biological properties of VWF, including the structural and functional characteristics of specific domains. The mechanism of interaction between the VWF A1 domain and glycoprotein Ibα has been elucidated in detail, bringing us closer to understanding how this adhesive bond can oppose the fluid dynamic effects of rapidly flowing blood contributing to platelet adhesion and activation. Moreover, novel findings have been obtained on the link between regulation of VWF multimer size and microvascular thrombosis. This progress in basic research has provided critical information to define with greater precision the role of VWF in vascular biology and pathology, including its possible involvement in the onset of atherosclerosis and its acute thrombotic complications.  相似文献   
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Variant von Willebrand disease designated as type I New York or type Malmö is characterized by enhanced ristocetin-induced platelet agglutination with normal von Willebrand factor multimeric distribution in plasma. We have studied four such patients belonging to three unrelated families and found in all of them a unique cytosine-to-thymine transition changing the codon for Pro503 (CCG) to Leu (CTG). In three patients the mutant allele also had a silent mutation in the codon for Ser500 (TCG-->TCA). Both nucleotide changes are present in the von Willebrand factor pseudogene; however, the characterization of distinctive markers where the gene and pseudogene differ, as well as the examination of amplified cDNA derived from platelet mRNA, confirmed that the abnormality occurs in the von Willebrand factor gene of the patients. Moreover, recombinant expression of the isolated glycoprotein Ib-binding domain of von Willebrand factor provided direct evidence that the Pro503-->Leu mutation is responsible for enhanced platelet reactivity to lower ristocetin concentrations. These results define a new structural element affecting the affinity of von Willebrand factor for glycoprotein Ib and establish the molecular basis of a variant form of von Willebrand disease.  相似文献   
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A panel of neutralizing IgA monoclonal antibodies was produced from mice orally inoculated with poliovirus type 3 Sabin and cholera toxin as adjuvant. Low levels of neutralizing antibodies were elicited in mice after several boosts, but only in the presence of cholera toxin. Characterization of IgA MAbs by neutralization-escape virus mutants showed that all but one neutralizing MAbs against type 3 poliovirus were directed to antigenic site N-AgIII, which was previously found by us to be the major target of mucosal immune response to Sabin 1 in the mouse. Our data indicate that residue 236 of VP3, not previously reported, is also involved in forming site N-AgIII in addition to formerly described VP3 (aa 58-59) and VP1 (aa 286-290) residues. Unlike poliovirus type 1 IgA MAbs, all IgA MAbs herein described neutralized the wild-type parental poliovirus.  相似文献   
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Uvomorulin (E-cadherin), a cell adhesion molecule, and Na+,K(+)-adenosine triphosphatase (ATPase), a marker protein of the basal-lateral cell membrane domains of polarized epithelial cells, were investigated in a group of mouse skin tumors induced by a two-stage chemical carcinogenesis protocol and in cell lines derived from mouse skin papillomas and squamous cell carcinomas (SCC). Although these two markers were present in benign tumors and in nontumorigenic cell lines, the Na+,K(+)-ATPase showed an altered pattern of distribution that included the presence of enzyme not only in the basolateral domain but also on the apical domain of the cell membrane of basal and spinous cells in well-differentiated squamous cell carcinomas (SCC). In higher grade SCC, a loss of Na+,K(+)-ATPase immunoreactivity was simultaneously detected with a marginal or absent expression of uvomorulin. The more differentiated SCC and papillomas expressed less uvomorulin immunoreactivity than normal epidermal cells. Both markers were seen in tumor cell lines that produced well-differentiated SCC after subcutaneous inoculation into nude mice. Neither Na+,K(+)-ATPase nor uvomorulin could be detected in cell lines that produced high grade, poorly differentiated SCC. Northern blots confirmed the absence of uvomorulin mRNA in these highly malignant cell lines. These data indicate that progression from premalignant papilloma to low-grade SCC and subsequently to high-grade SCC is accompanied by loss of epithelial cell polarity as detected by changes in Na+,K(+)-ATPase and by decreased or absent expression of uvomorulin in tumors and cell lines characterized by an advanced malignant phenotype.  相似文献   
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BACKGROUND: Subjective quality of life has gained a crucial role as a global measure of outcome in mental health care. This study aimed to investigate the impact of meeting needs for care, as assessed by both patients and mental health professionals, to improve the subjective quality of life in a sample of patients receiving community-based psychiatric care. METHOD: The study was conducted using a 4-year prospective longitudinal design. A cohort of patients from the South-Verona Community-based Mental Health Service (CMHS) was assessed at baseline and follow-up using, among other social and clinical measures, the Camberwell Assessment of Need (both staff and patient versions) and the Lancashire Quality of Life Profile. Predictors of changes of subjective quality of life were explored using block-stratified multiple regression procedures. RESULTS: Improvement in patients' clinical conditions as well as the reduction in patient-rated unmet needs in the social domain predicted an increase in subjective quality of life over 4 years; changes in staff-rated needs did not show any association with changes in subjective quality of life. CONCLUSIONS: Meeting self-perceived social needs, beyond symptoms reduction, seems to be of particular importance for ensuring a better quality of life for people with mental disorders. If the main goal of mental health care is to improve the quality of life of users, a policy of actively addressing patient-rated needs should be implemented.  相似文献   
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